Shingo Kasai

Ile-Lys-Val-Ala-Val (IKVAV)-containing laminin α1 chain peptides form amyloid-like fibrils

The Ile‐Lys‐Val‐Ala‐Val (IKVAV) sequence derived from laminin‐1 promotes cell adhesion, neurite outgrowth, and tumor growth and metastasis. Here, we examined amyloid formation of an IKVAV‐containing peptide (LAM‐L: AASIKVAVSADR, mouse laminin α1 chain 2097–2108). The LAM‐L peptide was stained with Congo red and exhibited fibrils in electron microscopy with a characteristic cross‐β X‐ray diffraction pattern. Further, infrared spectra of LAM‐L suggested a β‐sheet structure. These results indicate that LAM‐L forms amyloid‐like fibrils. We also examined amyloid‐like fibril formation of LAM‐L analogs. The neurite outgrowth activity of the LAM‐L analogs was closely related to their amyloid‐like fibril formation.

How laminin-1 can be recognized by the protozoan parasite Tritrichomonas foetus: possible role played by the extracellular matrix glycoprotein in both cytoadhesion and cytotoxicity exerted by the parasite.

The isoform 1 of the extracellular matrix glycoprotein Laminin is known to be an important ligand for some parasitic protozoa including Trichomonas vaginalis. The bovine parasite Tritrichomonas foetus seems to display a similar recognition process to laminin-1, as some amino acid sequences found in the LNS module of laminin-1 can also be recognized by this parasite. Which of the laminin-1 residing adhesion sequences are recognized by T. foetus, and the role played by such a protein-cell recognition process in both cytoadhesion and cytotoxicity exerted by the parasite are the subjects briefly reviewed and discussed here.